Increased concern from the public on issues of water quality has resulted in an explosion of water filtration devices on the market, particularly for household use. A popular household water filtration device is in the style of a pour-through pitcher. Typically, unfiltered water is added to a basin at the top of the device. Through the action of gravity, water percolates through a filtering media (usually consisting of granulated activated carbon) located between the basin and a collection reservoir. Filtered water is then dispensed from the collection reservoir for drinking. For the general public, gravity-controlled pitcher-type water filtration systems are cost effective. Many such water filtration systems are provided under the Brita® brand name.
One limitation of this kind of device is the inability to filter out and destroy smaller organisms and microbes. Other devices have been provided that provide additional purification or sanitization. Such systems typically include a water reservoir of some sort to be used with a base unit having additional purification technology. That way, water filtered in the usual manner in the filtering media in the reservoir is further purified by the additional purification technology.
Many water sanitization systems make use of ozonation to purify water. Some industrial water treatment systems include an air dryer comprising a desiccant provided in a reusable container, in order to increase efficiency of the ozonation process. The desiccant dries the air to remove moisture, typically in order to prevent damage to system elements. However, it is also known that dry air reacts better in an ozone generator, yielding better ozone concentration output. Often, the desiccant is separated into two storage areas, so that one portion of the desiccant is regenerated, while another portion of the desiccant is employed to dry the air. Regeneration is desired in industrial systems because of the large amount of desiccant used, and can be achieved by heating, refrigeration, or other approaches.
However, it can be impractical to attempt to use the regeneration approach of industrial systems in a small enterprise water treatment product. The term “small enterprise” as used herein represents an application that is low-volume and has a low number of users as compared to an industrial or municipal product. A small enterprise includes a small office, a division or branch of a large institution, a household, or any other environment that would be considered to be a consumer market.
Test research has shown that the procedure to regenerate desiccant material for a small enterprise water treatment system is generally too difficult for a small enterprise user, or consumer. It would typically require heating the desiccant in an oven under very strict constraints, and it was found that heating in a microwave does not yield proper results. Moreover, attempting to use the regeneration process could result in the small enterprise user misusing the product, and would likely be harmful to health, either by way of the regeneration process itself, or due to using the supposedly regenerated desiccant. Some ozone systems have expressly written off the use of air dryers in household or small commercial products due to the complications introduced by the regeneration process.
Known air dryers for industrial systems, which are primarily directed to drying compressed air, have valves in order to selectively restrict flow of air into the chamber housing the desiccant. These valves, often implemented as control valves, are used in order to perform the purging, vacuum and regeneration steps. Control valves are also used to prevent prolonged exposure of the desiccant to atmospheric air. If a desiccant is exposed to atmospheric air for too long a period of time, the desiccant gets used up too quickly and loses its effectiveness as a desiccant.
There are, therefore, issues with industrial applications of air dryers in water treatment systems that need to be resolved before the concepts in such systems can be used in a product intended for small enterprise use.
It is, therefore, desirable to provide a water sanitization system that overcomes at least one disadvantage of known water sanitization systems.